1. Field of the Invention
The present invention relates to a method for manufacturing a liquid crystal display device including a spacer.
2. Description of the Related Art
In a liquid crystal display device, in order to maintain the space (the gap) between substrates and control the thickness of a liquid crystal layer (cell gap), a columnar or spherical (bead) spacer is used.
Typically, a columnar spacer is formed in such a manner that a photosensitive resin is applied by spin coating or the like and processed into a columnar shape by a photolithography process. In that case, it is possible to control the position where a columnar spacer is formed in a liquid crystal display device, but it is difficult to uniformly control the thickness of the columnar spacer, which determines the thickness of a liquid crystal layer. In addition, the use of the photolithography process leads to low material-use efficiency, increased cost, and decreased productivity.
A spherical spacer (also referred to as a bead spacer) is generally dispersed in a liquid crystal display device by a distributor (for example, see Patent Document 1: Japanese Published Patent Application No. H11-352495). In a conventional method for providing a spacer, as illustrated in a flow chart of FIG. 4, an insulating layer functioning as an alignment film is formed, rubbing treatment is performed, a spherical spacer is dispersed by a dispersing method, substrates are attached to each other, and heat treatment is performed to fix the spherical spacer with an adhesive. However, in the conventional method illustrated in FIG. 4, it is difficult to control the position where the spherical spacer is arranged, and thus the spherical spacer is also provided in a display region. Accordingly, there may occur display defects such as damage due to movement of the spherical spacer, light leakage, and alignment disorder on the periphery of the spherical spacer. In order to control the position where a spherical spacer is arranged, it has been reported that a bead spacer is positioned by an ink jet method (for example, see Patent Document 2: Japanese Published Patent Application No. 2002-372717).